Coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been spreading worldwide since its outbreak in December 2019, and World Health Organization declared it as a pandemic on March 11, 2020. SARS-CoV-2 is highly contagious and is transmitted through airway epithelial cells as the first gateway. SARS-CoV-2 is detected by nasopharyngeal or oropharyngeal swab samples, and the viral load is significantly high in the upper respiratory tract. The host cellular receptors in airway epithelial cells, including angiotensin-converting enzyme 2 and transmembrane serine protease 2, have been identified by single-cell RNA sequencing or immunostaining. The expression levels of these molecules vary by type, function, and location of airway epithelial cells, such as ciliated cells, secretory cells, olfactory epithelial cells, and alveolar epithelial cells, as well as differ from host to host depending on age, sex, or comorbid diseases. Infected airway epithelial cells by SARS-CoV-2 in ex vivo experiments produce chemokines and cytokines to recruit inflammatory cells to target organs. Same as other viral infections, IFN signaling is a critical pathway for host defense. Various studies are underway to confirm the pathophysiological mechanisms of SARS-CoV-2 infection. Herein, we review cellular entry, host-viral interactions, immune responses to SARS-CoV-2 in airway epithelial cells. We also discuss therapeutic options related to epithelial immune reactions to SARS-CoV-2.Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes coronavirus disease 2019 (COVID-19), an ongoing pandemic disease. https://www.selleckchem.com/products/Rapamycin.html In the current review, we describe SARS-CoV-2-specific CD4+ and CD8+ T-cell responses in acute and convalescent COVID-19 patients. We also discuss the relationships between COVID-19 severity and SARS-CoV-2-specific T-cell responses and summarize recent reports regarding SARS-CoV-2-reactive T cells in SARS-CoV-2-unexposed individuals. These T cells may be cross-reactive cells primed by previous infection with human common-cold coronaviruses. Finally, we outline SARS-CoV-2-specific T-cell responses in the context of vaccination. A better understanding of SARS-CoV-2-specific T-cell responses is needed to develop effective vaccines and therapeutics.The emergence of a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has become a significant health concern worldwide. Undoubtedly, a better understanding of the innate and adaptive immune responses against SARS-CoV-2 and its relationship with the coronavirus disease 2019 (COVID-19) pathogenesis will be the sole basis for developing and applying therapeutics. This review will summarize the published results that relate to innate immune responses against infections with human coronaviruses including SARS-CoV-1 and SARS-CoV-2 in both humans and animal models. The topics encompass the innate immune sensing of the virus to the dysregulation of various innate immune cells during infection and disease progression.A simple, fast, and validated HPLC method was developed for the simultaneous quantization of five cardiovascular agents dopamine (DPM), dobutamine (DBM), phentolamine (PTM), furosemide (FSM), and aminophylline (APL) either in infusion samples or in an injection dosage form. The proposed method was achieved with a 150?mm?×?4.6?mm, 5.0?μm C18 column, by using a simple linear gradient. Mobile phase A was buffer (50?mM KH2PO4) and mobile Phase B was acetonitrile at a flow rate of 1.0?mL/min. The column temperature was kept at 30°C, and the injection volume was 20?μL. All analytes were separated simultaneously at a retention time (tr) of 3.93, 5.84, 7.06, 8.76, and 9.67?min for DPM, DBM, PTM, FSM, and APL, respectively, with a total run time of less than 15.0?min. The proposed method was validated according to ICH guidelines with respect to accuracy, precision, linearity, limit of detection, limit of quantitation, and robustness. Linearity was obtained over a concentration range of 12.0-240.0, 12.0-240.0, 20.0-200.0, 6.0-240.0, and 10.0-200.0?μg/mL DPM, DBM, PTM, FSM, and APL, respectively. Interday and intraday accuracy and precision data were recorded in the acceptable limits. The new method has successfully been applied for quantification of all five drugs in their injection dosage form, infusion samples, and for evaluation of the stability of investigated drugs in mixtures for endovenous use. The results of the stability study showed that mixtures of DPM, DBM, PTM, FSM, and APL in 5% glucose or 0.9% sodium chloride injection were stable for 48 hours when stored in polypropylene syringes at 25°C.Liensinine, an important alkaloid in lotus seed, exhibits multiple functions such as anti-AIDS, anticancer, antidepressant, and antihypertensive properties. In this study, a highly sensitive HPLC-MS/MS method was developed and validated for the quantification of liensinine in microvolume rat plasma as low as 45?μL. Chromatographic separation was carried out using a reverse-phase Gemini-C18 column (100?mm?×?3?mm i.d.?×?5?μm), and mass selective detection using multiple reaction monitoring was attained using an electrospray ionization source, which operated in the positive mode. Dauricine was used as the internal standard. The precursor-to-product ion transition m/z 611.15?&gt;?206.10 was selected for the detection of liensinine; m/z 625.25?&gt;?206.10 was used for the detection of dauricine. The developed method is linear over the concentration range of 0.05-1000?ng/mL with an excellent coefficient of determination (R 2?=?0.991). The recoveries ranged from 92.57% to 95.88% at three quality control levels. Intraday and interday precision and accuracy are less than 12.2% and 6.59%, respectively. The lower limit of quantification (LLOQ) is 0.05?ng/mL. The matrix effect was insignificant and acceptable. The validated method was successfully applied to the pharmacokinetic study of liensinine in rats. This method can be used for in vivo studies as well as quality control of traditional Chinese medicines and herbal tea containing liensinine alkaloid.